0323 Associations Between Sleep and Activity Patterns in the Mother-Child Dyad

Abstract

Introduction Animal studies show links between light-dark patterns in gestating dams and offsprings’ sleep and circadian rhythms. Activity patterns between mothers and infants show synchrony as early as 12 weeks postpartum. Our goal was to investigate maternal sleep/activity patterns at two points in the perinatal period and assess associations with activity in their young children. Methods Participants were 20 mother-child dyads recruited from previous studies. Mothers (age±SD = 31.7±5.5 years, range 21-40 years) wore wrist actigraphs during their 33rd week of pregnancy and 2nd week postpartum. Children (age±SD = 2.13±1.36 years, range 8 months-4.6 years) were assessed for 5 days and nights. Circadian patterns were analyzed using Maximum Entropy Spectral Analysis (MESA) to estimate best-fitting circadian period, tau. We used cosinor analysis to calculate rhythm amplitude, Midline Statistic of Rhythm (MESOR, representing mean activity), and acrophase (time of peak amplitude). We used circadian quotient (CQ; amplitude÷MESOR) to assess rhythm strength while normalizing for intersubject variation in activity levels. Autocorrelation, or degree to which data is consistent for a particular period, was calculated to analyze regularity of activity patterns. Results Mothers’ activity pattern autocorrelation was significantly correlated at the two time points (r=.530, p=.016), such that women with inconsistent activity patterns in pregnancy also demonstrated more irregularity at postpartum week 2. Child CQ correlated with age, with older children showing greater rhythm strength (r=.530, p=0.016). We observed a moderate correlation between mothers’ CQs during pregnancy and children’s CQs (r=.413,p=.07). In mother-child dyads, longer tau in mothers during pregnancy predicted lower autocorrelation of the child’s rhythm to a 24-hr period (r=-.520, p=.019). Finally, later maternal acrophase at postpartum week 2 was associated with longer tau in children (r=.504, p=.024). Conclusion These data show that associations between mother-child sleep/activity patterns may begin during pregnancy and support the notion that mothers’ perinatal sleep patterns could affect the health of both mothers and their children. Support Supported by R34MH104377, K23MH086689, the Seleni Institute, the Depression and Bipolar Disorder Alternative Treatment Foundation, and a Karen T. Romer Undergraduate Teaching and Research Award from Brown University.